Electrical characterization of current conduction in Au/TiO2/n-Si at wide temperature range

In this study, we have examined Au/TiO2/n-Si Schottky barrier diodes (SBDs), in order to interpret in detail the experimental observed non-ideal current–voltage–temperature (I–V–T) characteristics. I–V characteristics were measured in the wide temperature range of 80–400 K. TiO2 was deposited on n-Si substrate by reactive magnetron sputtering. The zero-bias barrier height (ϕB0) and ideality factor (n) show strong temperature dependence. While n decreases, ϕB0 increases with increasing temperature. Experimental results show that the current across the SBDs may be greatly influenced by the existence of Schottky barrier height (SBH) inhomogeneity. These temperature behaviors have been explained on the basis of the thermionic emission (TE) theory with Gaussian distribution (GD) of the barrier heights (BHs) due to BH inhomogeneities at metal–semiconductor (M/S) interface. From this assumptions, obtaining Richardson constant value of the A* 121.01 A/cm2 K2 is perfect agreement with the theoretical value of 120 A/cm2 K2 for n-type Si. Hence, behaviors of the forward-bias I–V characteristics of the Au/TiO2/n-Si (SBDs) can be successfully explained on the basis of a TE mechanism with a double Gaussian distribution of the BHs.